The present invention relates to a dovetail jointing press for the manufacture of dovetail joints (finger joints) of boards that at their faces or ends are provided with respective dovetailings (fingers) by a cutting tool whereby the dovetailings (fingers) are pasted with glue.
With dovetail cutting tools, the faces of boards that are stacked on edge are cut to yield dovetailings (fingers) of a length of 10 to 30 cm. The dovetailings (fingers) are subsequently pasted with glue. The faces of the boards are then joint one after another in dovetail joints, and the boards, in the same plane, are pressed against one another in a press until the glue hardens. Thus, endless boards are created that are composed of individual boards of various lengths. The pasting must have the same strength as the natural wood. The endless boards are then cut to length and the resulting boards are pasted and pressed to form laminated beams.
In conventional methods for a medium or high throughout, continuous presses are employed comprising an upper and a lower plate conveyer which transport the boards through the press in a frictionally connecting manner. Depending on the length of the dovetail (fingers), the pasting pressure must be in a range of 50 to 100 kg/cm.sup.2, i.e., the feeding pressure is in the range from 5,000 to 10,000 kg for a common board cross-section of 25 cm by 4 cm. When per minute 10 or more joints are formed from boards of a length of 4 to 5 m, the energy requirements are high. At a feeding rate of 50 m per minute, 45 kW are needed for a press generating a pressure of 5,000 kg and 90 kW for a press generating a pressure of 10,000 kg. In addition to the very high energy requirements, the design of such presses is very complicated. With cycle presses, the holding pressure to be exerted for jointing the two boards generally must be double the feeding pressure.
It is therefore an object of the present invention to provide a dovetail jointing press that requires less energy, is of a simple design and reduces the amount of space required for set-up and operation.